Prevent West Nile

As Wyoming's summer season nears, residents should take action to protect themselves from West Nile virus according to a Wyoming Department of Health representative.

"Preventing mosquito breeding and avoiding mosquito bites are common-sense steps everyone should take," said Emily Thorp, surveillance epidemiologist with the Infectious Disease Epidemiology Program at the Wyoming Department of Health.

West Nile virus (WNV) can cause potentially serious illness in humans. Mosquitoes spread the virus by feeding on infected birds and then biting people, other birds and animals. Wyoming has seen human cases of WNV reported as early as May and as late as October with late summer and early fall as the typical peak times.

Wyoming West Nile Virus Surveillance Summary,
January – October 2015
The West Nile Virus Surveillance Summary, 2015, contains data gathered from multiple sources
through both required and volunteer-based reporting methods. Data collection for the year 2015 began
January 1, 2015. Human infection data is gathered through mandatory reporting by physicians and
laboratories of infectious diseases on the Reportable Diseases and Conditions list (State Statute § 35-4-
107). Veterinary data (i.e. equine infections) is gathered through mandatory reporting by veterinary
laboratories and veterinarians to the Wyoming State Veterinarian within the Wyoming Livestock Board,
who voluntarily passed the information to the Wyoming Public Health Veterinarian. Avian mortality
data is gathered through the volunteer reporting by Wyoming Fish and Game, and the Wyoming Office
of the U.S. Bureau of Land Management. Data on positive mosquito pools and total pools tested is
gathered through the volunteer reporting of local city/county weed and pest management agencies, and
local city/county public health environmental services divisions. Census data for the calculation of
incidence rates in this document are provided by the U.S. Census Bureau, Population Division, 2013. The
standard population used for calculating age-adjusted incidence, was the U.S. population estimates from
the 2010 Census. This summary is divided into two sections: Statewide and County-Specific descriptive
statistics.
Statewide Descriptive Statistics
Table 1. Demographic characteristics of human West Nile Virus (WNV) cases in Wyoming, 2015 by
manifestation: all infections, West Nile Fever (WNF) or West Nile Neuroinvasive Disease (WNND).

"So the best and easiest thing a person can do to avoid infection with West Nile virus is to abide by the 5'ds of prevention," Thorp said. The "5 D's" of prevention are:

1) DAWN and 2) DUSK - Most mosquito species prefer to feed at dawn or dusk, so avoid spending time outside during these times.
3) DRESS - Wear shoes, socks, long pants and a long-sleeved shirt when spending time outdoors or when mosquitoes are most active. Clothing should be light-colored and made of tightly woven materials to keep mosquitoes away from the skin.
4) DRAIN - Mosquitos breed in shallow, stagnant water. Reduce the amount of standing water by draining and/or removing it.
5) DEET - Use an insect repellent containing DEET (N, N-diethyl-m-toluamide). When using DEET, be sure to read and follow the instructions on the product's label. Other insect repellents such as Picaridin (KBR 3023) or oil of lemon eucalyptus can also be effective.

Property owners should also act to reduce mosquito breeding grounds:

Use smart landscaping to eliminate standing water that collects.

Repair failed septic tanks.

Dispose of containers that collect water such as tin cans, ceramic pots, or plastic containers.

Remove or discard old tires.

If you cannot dispose of old tires, drill holes in them to allow water to drain.

For containers such as bird baths or troughs, replace all of the water at least once a week.

Repair leaky water pipes and outdoor faucets.

Ensure that roof gutters drain properly.

Turn over plastic wading pools and wheelbarrows when not in use.

Cover trash containers to keep water out.

Aerate ornamental ponds or stock them with predatory fish.

Clean and chlorinate outdoor swimming pools even when not in use.

Keep drains, ditches, and culverts free of grass clippings, weeds, and trash so water will drain properly.